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121.
Results of a study are reported on the utilization of ground vulcanizate, which is a waste product of rubber prcoessing plants. Loaded stocks of various commercial rubbers act as objects for the study. Talc, kaolin, silicon dioxide, and furnace carbon black are used as fillers. According to the results of a study on the effect of the amount of rubber crumb, an increase in the content of unmodified crumb leads to a decrease in tear resistance that is associated with poor wettability. To increase wettability, we use organosilicon couplings. It is shown that the addition of vulcanizate to rubber stocks, together with highly dispersed fillers treated with organosilicon couplings, leads to a significant increase in tear resistance and makes it possible to significantly reduce the cost of production and utilization. 相似文献
122.
V. G. Kashakashvili S. Ya. Kurashvili A. G. Gordeziani A. N. Gagnidze 《Metallurgist》2006,50(1-2):36-38
A unit for making L-class high-strength pump-compressor tubing composed of low-carbon, low-alloy steels of type 15GFB is now
being used on the 140 mill in the tube-rolling shop at the Rustavi Metallurgical Plant. The steel 15GFB pump-compressor tubing
made by the technology that was developed has the following service properties: σy = 630–670 N/mm2, σu = 730–780 N/mm2, δ = 18–22%, ψ = 55–60%, KCU = 1.6–2.2 MJ/m2. The percentage of ductile fracture at room temperature is 85–95%.
__________
Translated from Metallurg, No. 1, pp. 79–80, January, 2006. 相似文献
123.
124.
Correlations between each of two parameters of empirical relationships describing arrays of experimental data on the long-term strength, creep, multi- and low-cycle fatigue, and the growth of fatigue cracks are established. Well-defined relationships between parameters within each array make it possible to reduce significantly the required volume of material tests. The physical essence of the observed correlations is associated with the thermally active nature of damage processes, which accompany each form of material tests. It is demonstrated that the pattern of the dependence of correlating empirical parameters on fundamental characteristics of thermally activated damage processes can be established for all types of tests under consideration: the height of the potential barrier, the frequency factor, etc. For all types of tests, analytical predictions are in good qualitative agreement with correlations observed in experiment.Translated from Problemy Prochnosti, No. 6, pp. 3–9, June, 1994. 相似文献
125.
O. Ya. Shmelev 《Measurement Techniques》1994,37(2):205-208
A measurement and computing system designed for acoustical investigations of liquid crystals, magnetic fluids, etc., in the frequency range 0.15–1.2 MHz is described.Translated from Izmeritel'naya Tekhnika, No. 2, pp. 51–53, February, 1994. 相似文献
126.
J. excelsa , J. foetidissima and J. oxycedrus. Among the compounds the monoterpenes exist in minor amounts while the sesquiterpenes including their oxygenated members
as well as sesquiterpene alcohols consist of the majority of the whole substances. The existence of some compounds of the
oils might be attributes of the species and their sap- and heartwood. On the other side though notable differences, the essential
oils of Turkish juniper woods resemble the commercial cedar wood oils.
This work was supported by the research found of the Istanbul University. Project nr: 1335/280799. 相似文献
Die Zusammensetzung der flüchtigen Extraktstoffe im Holz von Juniperus foetidissima und Juniperus oxycedrus
J. excelsa , J. foetidissima und J. oxycedrus. Monoterpene bilden einen geringen Anteil der Extraktstoffe. Der Hauptteil besteht aus Sesquiterpenen mit deren Oxydationsprodukten. Das Vorkommen einiger der ?le k?nnte charakteristisch sein für die jeweilige Art bzw. deren Splint- und Kernholz Allerdings gleichen diese ?le, trotz geringer Unterschiede, den wesentlichen ?lbestandteilen von Kommerziellen Zedernh?lzern.
This work was supported by the research found of the Istanbul University. Project nr: 1335/280799. 相似文献
127.
128.
Egorov G. F. Afanas'ev O. P. Zilberman B. Ya. Makarychev-Mikhailov M. N. 《Radiochemistry》2002,44(2):151-156
Experiments were performed for comparative assessment of the effect of ionizing radiation on the service characteristics of 30% TBP solutions in various diluents: hexachlorobutadiene (HCBD), mixtures of n-paraffins (RED diluent), and fraction of naphthenic hydrocarbons (RZh diluent). The following main parameters were chosen for comparative assessment of the quality of irradiated extractant solutions: composition and behavior of diluent radiolysis products, effect of diluents on the TBP radiolysis, and aggregative stability of emulsions in the main operations of the extraction cycle. The service life of the extraction mixtures was estimated from variation of the above parameters with the irradiation dose. Principles for choosing solvents with increased service life under irradiation were substantiated. 相似文献
129.
E. V. Grabovski M. K. Krylov V. V. Kuznetsov A. P. Lototsky E. V. Khaustov Yu. A. Khalimullin N. Yu. Kas'yanov A. I. Kormilitsyn V. A. Filatov E. Ya. Shkol'nikov 《Instruments and Experimental Techniques》2002,45(1):67-70
An inductive power-amplifier stage based on a two-coil assembly and two electrically exploded conductors used as circuit breakers is described. Owing to the magnetic flux conservation, the interruption of the current in the first of the storage coils causes an increase of the current in the second coil, which results in a rapid thermal burst of the second electrically exploded conductor. As a result, the load-current rise-time is 20 times less than the charging-current rise time and the amplitude of the current increases. 相似文献
130.
We study analytically and numerically the interaction of vortices in current-carrying narrow superconducting strips. The characteristic time of vortex-antivortex pair annihilation and the energetic losses in the strip are evaluated as a function of the external transport current and width of the strip. The effects of an external magnetic field on the motion of a single vortex are discussed. 相似文献